But she has just died, and to my sadness and surprise I didn't even know she was still alive.

Etta James, the black American blues singer, possessed a voice that could break brick walls and heartstrings alike.

I first became aware of her, I am ashamed to admit, courtesy of a TV ad for Jaguar motor cars in the early 1990s.

The ad's theme song spoke to me with a clarity and power that sent me scurrying to find out who sang it.

The song was At Last.

I sought out the full version, as well as Etta's multitude of other hits.

I became a big fan.

But because she seemed to have been around forever, having recorded hits in the 1950s, I assumed she had long passed on to that smoky nightclub in the sky.

So reading her death notice was, for me, one of those John Lennon moments.

I sang that song in my head.

At Last is one of those joyful/sorrowful songs about the relief of finding a soul mate.

It's about the discovery that there is someone out there who fits you like a jigsaw piece.

The opening lyric is spare and direct:

"At last my love has come along.

My lonely days are over,

And life is like a song."

The middle eight gets me, too:

"I found a dream that I could speak to,

A dream to call my own.

I found a thrill to press my cheek to,

A thrill that I had never known."

The combination of lyrics, the grand violin orchestration and Etta's sultry, sensitive and powerful vocals left me feeling elated but winded.

It must have had much the same effect on my wife.

It became "our song", not by any formal vote but by mutual consent, and it still is.

I have learned so much in this woman's death after she had been alive right under my nose all this time.

The Times obituary said she "allied a voice that could scream, belt, ache, growl, purr and cry to an indomitable spirit, generosity of heart and a dignity that belied the fact she had led a deeply troubled life".

Her mother was an unmarried 14-year-old; she never knew her father.